Infusion device comprising a pumping mechanism

ABSTRACT

An infusion device ( 1 ) for administering a medical fluid to a patient (P) comprises a pumping mechanism ( 4 ) configured to act onto a fluid conduit ( 20 ), the pumping mechanism ( 4 ) comprising a pumping section ( 42 ) movable with respect to said fluid conduit ( 20 ) for causing a fluid flow (F) through said fluid conduit ( 20 ). The pumping mechanism ( 4 ) comprises a multiplicity of rotatable gear elements ( 45 A- 45 E) coupled to the pumping section ( 42 ) at a multiplicity of different locations ( 43 A- 43 E), wherein the gear elements ( 45 A,  45 E) are operatively coupled to each other for a coordinated rotation of the gear elements ( 45 A- 45 E) for moving the pumping section ( 42 ). In this way an infusion device is provided which may allow for a small-sized pumping mechanism, yet providing for a reliable and efficient infusion operation.

The invention relates to an infusion device for administering a medicalfluid to a patient according to the preamble of claim 1 and to a methodfor operating an infusion device.

An infusion device of this kind comprises a pumping mechanism configuredto act onto a fluid conduit, the pumping mechanism comprising a pumpingsection movable with respect to said fluid conduit for causing a fluidflow through said fluid conduit.

An infusion device of this kind is generally denoted as a volumetric(peristaltic) infusion pump. The pumping mechanism herein in aperistaltic fashion acts onto a fluid conduit, for example an infusionline, for transporting a medical fluid through the fluid conduit inorder to deliver the medical fluid towards a patient.

A peristaltic infusion device as commonly known in the prior art forexample comprises a pumping mechanism having a multiplicity of pumpfingers for sequentially acting onto a fluid conduit in order to forcefluid in a specified pumping direction through the conduit. Otherperistaltic infusion devices use for example a wobble device whichperforms a wobbling action for acting onto a pump module comprising amembrane, the wobbling action causing a fluid to flow through the pumpmodule.

There is a general desire to provide a peristaltic infusion device whichmay comprise a pumping mechanism of small size and easy construction,yet providing for a reliable and efficient pumping action.

WO 2012/049263 A1 discloses an infusion device comprising a pumpingmechanism having a wobble mechanism for acting onto a pump module. Awobbling disc herein is connected at a slanted angle to a rotationalshaft such that by rotating the shaft the wobbling disk can be moved toact onto a membrane of the pump module.

From WO 2010/088143 A1 a peristaltic infusion device is known whichcomprises a pumping mechanism having roller elements being placed on acommon carrier element, the roller elements being configured to act ontoa fluid conduit by rotating the carrier element in order to transportfluid through the fluid conduit.

It is an object of the instant invention to provide an infusion deviceand a method for operating an infusion device which may allow for asmall-sized pumping mechanism, yet providing for a reliable andefficient infusion operation.

This object is achieved by means of an infusion device comprising thefeatures of claim 1.

Accordingly, the pumping mechanism comprises a multiplicity of rotatablegear elements coupled to the pumping section at a multiplicity ofdifferent locations, wherein the gear elements are operatively coupledto each other for a coordinated rotation of the gear elements for movingthe pumping section.

The pumping mechanism hence is designed to act onto a pumping section bymeans of a multiplicity of rotatable gear elements. The gear elementsare coupled to the pumping section such that by rotating the gearelements the pumping section is moved in order to cause a fluid flowthrough the fluid conduit in order to administer a medical fluid to apatient.

The gear elements herein are operatively coupled to each other and henceform a gear train which ensures a coordinated rotation of the gearelements. Hence, the gear elements are rotated together such that thegear elements cannot be rotated independently of each other. Rather, arotation of one gear element goes along with a rotation of all othergear elements, the rotation of the gear elements taking place in acoordinated fashion such that each gear element is moved in a definedmanner if the other gear elements are rotated.

The gear train formed by the gear elements may for example be driven bya single drive device, for example in the shape of an electric motor.For this, the drive device may act onto one of the gear elements, therotation of the one gear element causing a rotation of all other gearelements in a defined, coordinated fashion.

The gear elements may be mechanically coupled to each other for exampleby a meshing engagement. Alternatively, an electronic coupling isconceivable by rotating the gear elements by separate drive devices, thedriving however being coordinated such that the gear elements arerotated together in a coordinated fashion.

The gear elements beneficially each are coupled to the pumping sectionsuch that each gear element acts onto the pumping section. The gearelements may be aligned along a longitudinal flow direction along whichthe fluid conduit extends, pivot axes of the gear elements extendingtransverse to the longitudinal flow direction and being displaced withrespect to each other along the longitudinal flow direction.

The gear elements herein may be coupled to the pumping section such thatthe gear elements act onto the pumping section at locations which aredisplaced with respect to the each other along the longitudinal flowdirection such that by means of the gear elements a sequential,peristaltic movement of the pumping section is possible for transportingfluid through the fluid conduit.

In one embodiment, each of the gear elements comprises a toothing suchthat a meshing engagement with other gear elements may be established.The gear train may be formed by neighbouring gear elements directlymeshing with each other. Alternatively, one or multiple additional toothwheels may be arranged between neighbouring gear elements such thatneighbouring gear elements are coupled to each other indirectly viatooth wheels placed therebetween.

In one embodiment, neighbouring gear elements of the multiplicity ofgear elements are operatively coupled to each other such that theneighbouring gear elements are operative to rotate in oppositerotational directions. For this, neighbouring gear elements may forexample be in direct meshing engagement, such that a rotation of onegear element causes a rotation of a neighbouring gear element in anopposite rotational direction. Neighbouring gear elements hence arerotated in an opposite fashion, a rotation of one gear element in aclockwise direction for example causing a rotation of a neighbouringgear element in a counterclockwise direction.

In another embodiment neighbouring gear elements of the multiplicity ofgear elements are operatively coupled to each other such that theneighbouring gear elements are operative to rotate in equal rotationaldirections. In this case, between neighbouring gear elements anadditional tooth wheel may be arranged such that the neighbouring gearelements are coupled to each other by means of the intermediary toothwheel. In this case the neighbouring gear elements rotate in equaldirections, the rotation of one gear element for example in theclockwise direction causing a rotation of a neighbouring gear elementalso in the clockwise direction.

Generally, one or multiple tools wheels may be arranged in betweenneighbouring gear elements, such that the neighbouring gear elements maybe coupled to each other by means of one or multiple intermediary toothwheels. The gear train hence is formed by the gear elements inconnection with the tooth wheels, the gear elements herein being coupledto the pumping section such that a rotation of the gear elements causesa movement of the pumping section for transporting a fluid through thefluid conduit.

In one embodiment, the pumping mechanism comprises a multiplicity ofconnecting elements connecting the gear elements to the pumping section,each connecting element being connected to the pumping section at one ofthe multiplicity of different locations. The gear elements hence arecoupled to the pumping section by means of different connectingelements, for example having the shape of rods, such that a rotationalmovement of the gear elements is transferred to a movement of thepumping section, the connecting elements hence acting for transferringthe movement of the gear elements in a defined manner into a specifiedmovement of the pumping section for causing a pumping action at thefluid conduit.

Each of the gear elements herein may be coupled to one of the connectingelements. A connecting element for example may be coupled to theassociated gear element in a pivotable manner such that during rotationof the gear element the connecting element may pivot with respect to thegear element.

The connecting element specifically may be coupled to the associatedgear element in an eccentric manner. In particular, each gear elementmay be rotatable about an associated rotational axis, the connectingelement being coupled to the associated gear element at a couplinglocation eccentric to the rotational axis. When rotating the gearelement, hence, the coupling location in an eccentric fashion rotatesabout the rotational axis, hence causing a planetary movement of thecoupling location around the rotational axis and a correspondingmovement of the connecting element. Such movement of the gear elementsis transferred, via the connecting elements, to the pumping section,such that the pumping section is moved in a way such that fluid isforced to flow through the fluid conduit.

The coupling location of each gear element may be arranged in apredefined manner with respect to the coupling locations of other gearelements such that the pumping section is caused to move in aperistaltic fashion for forcing fluid through the fluid conduit. Forexample, the coupling location of a first gear element of themultiplicity of gear elements may be displaced along a firstdisplacement direction from the rotational axis of the first gearelement, whereas the coupling location of a second gear element of themultiplicity of gear elements is displaced along a second displacementdirection from the rotational axis of the second gear element, the firstdisplacement direction and the second displacement direction beingangularly offset with respect to each other.

Beneficially, herein, the angular offset between the displacementdirections of the first gear element and the second gear element remainsconstant during rotational movement of the gear elements.

In case neighbouring gear elements perform opposite rotationalmovements, no constant offset between the neighbouring gear elementsexist. Herein, however, beneficially the displacement directions of afirst gear element and a second gear element have a defined angularoffset which are not directly neighbouring, but have one intermediarygear element placed therebetween. The first gear element and the secondgear element rotate in equal rotational directions, whereas theintermediary gear element will rotate in an opposite rotationaldirection. In this case, hence, gear elements which are not directlyneighbouring each other may have a predefined angular offset withrespect to the coupling locations of their connecting elements.

In case neighbouring gear elements perform equal rotational movementsand hence rotate in equal rotational directions, there beneficially is aconstant angular offset between the displacement directions of thecoupling locations of the connecting elements for the directlyneighbouring gear elements.

By choosing a suitable angular offset with respect to the couplinglocations for coupling the connecting elements to the gear elements, asuitable transfer of movement to the pumping section can be achieved,the movement of the pumping section being such that a peristaltic pumpaction at the pump section is obtained.

In one embodiment, the pumping section comprises a multiplicity ofpumping elements, wherein neighbouring pumping elements of themultiplicity of pumping elements are pivotably coupled to each other atan associated pivot axis. The pumping section hence is formed by a chainof pumping elements pivotably coupled to each other, the pumpingelements for example being formed by rigid beam sections forming a chainof pumping elements.

In this case each gear element may for example, by means of itsassociated connecting element, act onto a pivot axis in betweenneighbouring pumping elements, the gear elements beneficially actingonto different pairs of pumping elements such that each gear elementacts onto the chain of pumping elements at a distinct pivot axis of apair of neighbouring pumping elements. By rotational movement of thegear elements, hence, the chain of pumping elements can be moved inorder to act onto the fluid conduit for forcing a fluid flow through thefluid conduit.

In another embodiment the pumping section may be formed by a flexiblydeformable wall element, which beneficially may be integrally shaped andfabricated from an elastomeric material. The pumping section hence isformed as one piece, which may be flexibly deformed by movement of thegear elements, the gear elements for example being linked to the pumpingsection by means of connecting elements integrally connected to thepumping section.

The object is also achieved by means of a method for operating aninfusion device for administering a medical fluid to a patient, themethod comprising: acting, by means of a pumping mechanism, onto a fluidconduit, the pumping mechanism comprising a pumping section movable withrespect to said fluid conduit for causing a fluid flow through saidfluid conduit, and moving the pumping section using a multiplicity ofrotatable gear elements of the pumping mechanism, wherein the rotatablegear elements are coupled to the pumping section at a multiplicity ofdifferent locations and are operatively coupled to each other such thatthe gear elements perform a coordinated rotation when moving the pumpingsection.

The advantages and advantageous embodiments described above for theinfusion device equally apply also to the method, such that in thisrespect it shall be referred to the above.

The idea underlying the invention shall subsequently be described inmore detail with reference to the embodiments shown in the figures.Herein:

FIG. 1 shows a schematic drawing of an arrangement of infusion devicesat the bedside of a patient;

FIG. 2 shows a schematic drawing of an infusion device configured as avolumetric (peristaltic) infusion device;

FIG. 3 shows a schematic drawing of a pumping mechanism of an infusiondevice;

FIG. 4A to 4E show the pumping mechanism in different states duringactuation for pumping a fluid through a fluid conduit;

FIG. 5 shows a schematic drawing of another embodiment of a pumpingmechanism of an infusion device; and

FIG. 6 shows a schematic drawing of angular offsets of couplinglocations at which connecting elements are connected to gear elements ofthe pumping mechanism.

Generally, as illustrated in FIG. 1, a multiplicity of infusion devices1 may be arranged at the bedside of a patient P for delivering one ormultiple medical fluids, such as medications, nutritional liquids, asaline solution or the like, to the patient P. The infusion devices 1may be arranged on a stand and each serve to deliver a medical fluidfrom a container 3 via an infusion line 2 towards the patient P.

An infusion device 1 as concerned herein in particular is configured asa volumetric (peristaltic) infusion pump for performing a peristalticpump action for transporting a fluid through an infusion line 2.

As schematically shown in FIG. 2, an infusion device 1 of this typegenerally may comprise a housing 10 having a front face 100 on which areceptacle 101 for receiving an infusion line 2 is formed. A closureelement 11 in the shape of a pivotable door may be connected to thehousing 10 and may be closed in order to securely receive and fasten aninfusion line 2 within the receptacle 101 formed on the front face 100of the housing 10.

The infusion device 1 comprises a pumping mechanism 4 for acting ontothe infusion line 2 or a pump module connected to the infusion line 2.The pumping mechanism 4 generally is configured to act onto the infusionline 2 in a peristaltic moving manner in order to force a fluid in aflow direction F through the fluid line 2 such that fluid is pumpedthrough the infusion line 2 generally from a container 3 towards apatient P.

Different embodiments of such a pumping mechanism 4 are shown in FIGS. 3to 5.

In one embodiment, as shown in FIG. 3, the pumping mechanism 4 comprisesa multiplicity of gear elements 45A-45E in the shape of toothed wheels,each gear element 45A-45E being rotatable about an associated rotationalaxis 450 and carrying a toothing 452 on its circumferential outer face.The gear elements 45A-45E herein are in meshing engagement with eachother in that a first gear element 45A meshes with a neighbouring,second gear element 45B, which additionally meshes with a neighbouring,third gear element 45C and so on. The gear elements 45A-45E hence arecoupled to each other to form a gear train 45, the gear train 45 beingsuch that the gear elements 45A-45E cannot be rotated independently ofeach other, but can be rotated only together in a coordinated fashion.

In the embodiment of FIG. 3, the first gear element 45A is linked to adrive device 46 for example in the shape of an electric drive motor, thefirst gear element 45A hence being driven, during operation, to rotate,hence causing the other gear elements 45B to 45E to rotate together withthe first gear element 45A.

The gear elements 45A are rotatably mounted for example with respect tothe housing 10.

The gear elements 45A-45E herein are coupled by means of correspondingconnecting elements 44A-44E in the shape of rod elements to a pumpsection 42 formed by a multiplicity of pumping elements 420-425 in theshape of beam sections pivotably coupled to each other at pivot axes43A-43E.

The connecting elements 44A-44E each, at a first end, are coupled totheir associated, respective gear element 45A-45E at a coupling location451, the coupling location 451 being eccentric to the respectiverotational axis 450 of the gear element 45A-45E.

At a second end each connecting element 44A-44E is coupled to a pivotaxis 43A-43E of a pair of neighbouring pumping elements 420-425.

The connecting elements 420-425 form a chain of beams pivotably coupledto each other. At one end 429 the chain of pumping elements 420-425herein is pivotably coupled to a fixed wall section 41, for example asection of the housing 10. At a second end 426 the chain of pumpingelements 420-425 is coupled to a coupling element 427 and via thecoupling element 427 is pivotably coupled at a pivot axis 428 forexample to the housing 10, the linkage at the end 426 allowing for alateral adjustment movement at the end 426 during movement of thepumping section 42 in order to adjust for a lateral movement at the end426 due to a change in shape of the pump section 42, as it will becomeapparent from FIGS. 4A to FIG. 4E.

The pumping section 42 serves to act onto a fluid conduit 20, which forexample is formed by an infusion line 2 received within the receptacle101 in between the housing 10 and the closure element 11 of the infusiondevice 1. The pumping section 42 herein, when moved by the gear elements45A-45E, is in a periodic fashion pinched at moving locations, forcingin a peristaltic fashion a flow of fluid along a flow direction Fthrough the fluid conduit 20.

FIGS. 4A to FIG. 4E show the pumping mechanism 4 of FIG. 3 in differentrotational states of the gear elements 45A-45E, denoted to states of 0°,90°, 180°, 270° and 360°, the state of FIG. 4E hence matching the stateof FIG. 4A, such that FIGS. 4A to 4E illustrate one complete revolutionof the gear elements 45A-45E.

When driving the gear train 45 of the gear elements 45A-45E, the gearelement 45A may for example be rotated, by means of an electric drive,in a counter clockwise rotational direction, as indicated in FIG. 3.This causes the neighbouring gear element 45B to rotate in a clockwisedirection, the gear element 45C in a counterclockwise direction, thegear element 45D again in a clockwise direction, and the gear element45E in a counterclockwise direction. During the rotational movement ofthe gear elements 45A-45E, herein, the coupling location 451 of eachgear element 45A-45E eccentrically rotates about the rotational axis 450of the associated gear element 45A-45E, such that the correspondingconnecting element 44A-44E is moved eccentrically about the rotationalaxis 450 of the corresponding gear element 45A-45E.

When viewing FIGS. 4A to 4E, it can be observed that the pump section 42causes locations of pinching P1, P2 at the fluid conduit 20, due to themovement of the gear elements 45A-45E, which move in the flow directionF and in this way force a fluid flow through the fluid conduit 20. Inparticular, when the coupling location 451 of a gear element 45A-45E isat a position pointing towards the fluid conduit 20, as it is the casein FIG. 4A for gear element 45D, the fluid conduit 20 will be pinched ata location of pinching P1 by the corresponding connecting element 44D.During rotational movement of the gear elements 45A-45E the location ofdepression P1, P2 moves in the flow direction F, as visible for thelocation of depression P1 in FIGS. 4A and 4B and for the location ofdepression P2 (following behind) in FIG. 4B to FIG. 4E. In this way,fluid is pushed through the fluid conduit 20, hence causing a fluid flowthrough the fluid conduit 20 in the flow direction F.

In the embodiment of FIG. 3 and FIGS. 4A to 4E neighbouring gearelements 45A-45E rotate in opposite rotational directions. The couplinglocations 451 of the gear elements 45A-45E herein, as visible from FIG.4A to FIG. 4E, are generally angularly offset with respect to eachother, hence causing a peristaltic pumping action at the pump section42.

As visible herein, gear elements 45A-45E rotating in the same rotationaldirections maintain their angular offset. For example, the gear elements45A and 45C, at their coupling locations 451, have an offset of 180°,which is maintained during rotation of the gear elements 45A-45E, asvisible from FIG. 4A to 4E.

This schematically is illustrated in FIG. 6. The coupling locations 451at which the associated connecting element 44A-44E is coupled to therespective gear element 45A-45E is displaced with respect to therotational axis 450 along a displacement direction X1-X5, the differentdisplacement directions X1-X5 having generally an angular offset withrespect to each other. The angular offset between the displacementdirections X1-X5 between the gear elements 45A-45E rotating in the samerotational direction (for example gear elements 45A and 45C or gearelements 45B and 45D) herein remains constant during rotational movementof the gear elements 45A-45E.

As visible from FIG. 4A to 4E, the axial length of the chain of pumpingelements 420-425 changes as the pumping elements 420-425 are moved bythe gear elements 45A-45E. The change in axial length herein is adjustedby the coupling of the chain of pumping elements 420-425 at the end 426by means of the coupling element 427, which is pivotably connected tothe housing 10 at the pivot axis 428 and hence allows for an axialmovement of the endpoint 26, as apparent for example from the transitionfrom FIG. 4A to FIG. 4B.

In another embodiment illustrated in FIG. 5, the pumping mechanism 4comprises a pumping section 42 formed by an integral wall elementfabricated for example from an elastomeric material and hence beingflexibly deformable. Connecting elements 44A-44E herein are integrallyformed with the pumping section 42, the pumping section 42 beingconnected to fixed wall sections 40, 41 at its ends 426, 429.

As explained above according to the embodiment of FIGS. 3 and 4A to 4Egear elements 45A-45E are coupled to the pumping section 42 by means ofthe connecting elements 44A-44E. Herein, however the gear elements45A-45E in the embodiment of FIG. 5 are coupled to each other to rotatein equal rotational directions in that between neighbouring gearelements 45A-45E in each case an intermediary tooth wheel 47 is arrangedserving to couple neighbouring gear elements 45A-45E to each other. Eachgear element 45A-45E herein meshes (dependent on its location in thegear train 45) with one or two of the tooth wheels 47, such that thegear elements 45A-45E are coupled to each other to rotate together whendriving one of the gear elements 45A-45E by a drive device 46 forexample in the shape of an electric motor.

In the embodiment of FIG. 5 the coupling locations 451 of the connectingelements 44A-44E at the gear elements 45A-45E are displaced indisplacement directions which are angularly offset with respect to eachother, as apparent from FIG. 5. Herein, because the gear elements45A-45E are rotated in equal rotational directions the angular offset ofneighbouring gear elements 45A-45E remains constant during rotationalmovement of the gear elements 45A-45E.

Other than that the principle peristaltic function of the embodiment ofFIG. 5 is comparable to the function of the embodiment of FIGS. 3 and 4Ato 4E, such that it shall in this respect be referred to the above.

The idea underlying the invention is not limited to the embodimentsdescribed above, but may be implemented also in an entirely differentfashion.

An infusion device as described herein may be used to deliver differentmedical fluids, such as medication, nutritional liquid or the like,towards a patient.

The pumping mechanism of the infusion device herein may act onto aninfusion line, or a pump module connected to an infusion line in orderto exert a peristaltic pump action onto the infusion line.

LIST OF REFERENCE NUMERALS

-   1 Infusion device-   10 Housing-   100 Front face-   101 Receptacle-   11 Closure element-   2 Infusion line-   20 Fluid conduit-   3 Container-   4 Pump mechanism-   40, 41 Fixed wall section-   42 Deformable pumping section-   420-425 Pumping element (beam section)-   426 Coupling axis-   427 Coupling element-   428 Pivot axis-   429 Pivot axis-   43A-43E Location (pivot axis)-   44A-44E Connecting element-   45 Gear train-   45A-45E Gear element-   450 Rotational axis-   451 Coupling location-   452 Toothing-   46 Drive motor-   47 Tooth wheel-   F Flow direction-   P Patient-   P1, P2 Locations of depression-   X1-X5 Displacement direction

1. An infusion device for administering a medical fluid to a patient,comprising: a pumping mechanism configured to act onto a fluid conduit,the pumping mechanism comprising a pumping section movable with respectto said fluid conduit for causing a fluid flow through said fluidconduit, and a multiplicity of rotatable gear elements coupled to thepumping section at a multiplicity of different locations, wherein thegear elements are operatively coupled to each other for a coordinatedrotation of the gear elements for moving the pumping section
 2. Theinfusion device according to claim 1, wherein the multiplicity of gearelements each comprise a toothing for operatively coupling themultiplicity of gear elements to each other.
 3. The infusion deviceaccording to claim 1, wherein neighboring gear elements of themultiplicity of gear elements are operatively coupled to each other suchthat the neighboring gear elements are operative to rotate in oppositerotational directions.
 4. The infusion device according to claim 1,wherein neighboring gear elements of the multiplicity of gear elementsare operatively coupled to each other such that the neighboring gearelements are operative to rotate in equal rotational directions.
 5. Theinfusion device according to claim 1, wherein a tooth wheel is arrangedbetween neighboring gear elements of the multiplicity of gear elementsfor operatively coupling the neighboring gear elements to each other. 6.The device according to claim 1, wherein the pumping mechanism comprisesa multiplicity of connecting elements connecting the multiplicity ofgear elements to the pumping section, each connecting element beingconnected to the pumping section at one of the multiplicity oflocations.
 7. The infusion device according to claim 6, wherein eachgear element of the multiplicity of gear elements is coupled to oneconnecting element of the multiplicity of connecting elements.
 8. Theinfusion device according to claim 7, wherein each gear element of themultiplicity of gear elements is rotatable about an associatedrotational axis, the one connecting element of the multiplicity ofconnecting elements being pivotally coupled to the associated gearelement at a coupling location eccentric to the rotational axis.
 9. Theinfusion device according to claim 8, wherein the coupling location of afirst gear element of the multiplicity of gear elements is displacedalong a first displacement direction from the rotational axis of thefirst gear element, whereas the coupling location of a second gearelement of the multiplicity of gear elements is displaced along a seconddisplacement direction from the rotational axis of the second gearelement, wherein the first displacement direction and the seconddisplacement direction are angularly offset with respect to each other.10. The infusion device according to claim 9, wherein the angular offsetbetween the displacement directions of the first gear element and thesecond gear element remains constant during rotational movement of themultiplicity of gear elements.
 11. The infusion device according toclaim 6, wherein the multiplicity of connecting elements each are formedby a rod element.
 12. The infusion device according to claim 1, whereinthe pumping section comprises a multiplicity of pumping elements,wherein neighboring pumping elements of the multiplicity of pumpingelements are pivotally coupled to each other at an associated pivotaxis.
 13. The infusion device according to claim 12, wherein each gearelement of the multiplicity of gear elements is coupled to an associatedpair of neighboring pumping elements at the pivot axis of the associatedpair of neighboring pumping elements.
 14. The infusion device accordingto claim 1, wherein the pumping section is formed by a flexiblydeformable wall element.
 15. A method for operating an infusion devicefor administering a medical fluid to a patient, comprising: acting, bymeans of a pumping mechanism, onto a fluid conduit, the pumpingmechanism comprising a pumping section movable with respect to saidfluid conduit for causing a fluid flow through said fluid conduit, andmoving the pumping section using a multiplicity of rotatable gearelements of the pumping mechanism, wherein the multiplicity of rotatablegear elements are coupled to the pumping section at a multiplicity ofdifferent locations and are operatively coupled to each other such thatthe multiplicity of gear elements perform a coordinated rotation whenmoving the pumping section.